Banner of Command QoL Change / Buff
New: Promote can now also target a friendly Inhibitor. When used on an Inhibitor, the next Cannon Minion that spawns for that lane is Promoted automatically. CD begins when cast on Inhib, not when the Siege minion spawns.
Context: This saves travel time to go promote a minion for a lane you don't want to go to, and makes the 120 second CD more relevant, as you don't have to wait for the Siege wave to spawn. This is especially important earlier in the game because Siege minions spawn every 3 waves pre-20 minutes, every other at 20-35, and every wave at 35+.
+200 Health
+60 Ability Power
+20 Magic Resist
+10% Cooldown Reduction
UNIQUE Aura - Legion: Grants nearby allies +20 Magic Resist and +75% Base Health Regen. UNIQUE Active - Promote: Greatly increases the power of a lane minion and grants it immunity to magic damage (120 second cooldown).
The items is just too rarely used. If you buy an Aegis, it's usually because you want the MR aura and will eventually upgrade to Locket, not often because you want to increase your split pushing while not in lane.